This invention relates generally to a device for use in establishing desired grade levels on construction sites and, more particularly, to such a device that provides for machine operators a visible indication of the cut or fill that is required to establish the desired grade.
In many types of construction projects it is necessary to modify existing terrain while establishing new grade levels that are required for a specific purpose. Such grading operations can include either filling which entails the addition of material to the existing terrain so as to establish a higher grade level or cutting which entails the removal of material to establish a lower grade level. On most construction sites, grading is accomplished with earth moving equipment such as bulldozers. Typically, surveying equipment is utilized to establish indications of desired grade elevations on grade stakes located remotely from the surface being worked. Such grade stakes indicate the amount of cut or fill that is required relative to a given elevation marked on the stake. A grade foreman located in the area being worked utilizes a ruler and a hand level in conjunction with the grade stakes to determine the amount of fill or cut required in specific locations. In arriving at such a determination, the grade foreman must compare the reading obtained with his ruler to the required grade information indicated on the grade stake and calculate the actual amount of fill or cut that is required. Having established the type and degree of grading operation required, the grade foreman must transmit this information to the operator of a machine being used to reestablish desired grade levels. Typically, the transmission of grading information from the grade foreman to the machine operator is accomplished with various types of hand signals. Because of errors made either in the original grading calculations made by the grade foreman or in the transmission of correct information to a machine operator, certain passes by a machine operator often produce inaccurate cuts or fills. In addition, the requirements for both calculating and conveying desired grade change information often induces substantial delays between passes by an earth moving machine and thereby reduces the efficiency of a grading operation.
The object of this invention, therefore, is to provide a device that will obviate some of the problems associated with conveying grade level information to machine operators and thereby improve the efficiency of grading operations.